This invention relates generally to a fitting for piping associated with a fluid tank, line or other enclosure and relates more particularly to an aseptic sample fitting through which samples of fluid contained within the piping can be extracted.
In the production of viscous products, such as consumable fluids or various pharmaceuticals, in which the bacteria count must be maintained within predetermined levels, samples of the products are commonly taken at appropriate stages of the product production. Inasmuch as the products are commonly routed through a piping network joining the stages of production, sample fittings can be incorporated into the piping for the purpose of providing an access port through which samples of the product can be extracted. Such a sample fitting commonly includes a conduit portion attachable in-line with the piping and a neck portion joined to the conduit portion. The neck portion defines an opening therein providing access to the product contained within the conduit portion, and a cover is operatively securable to the neck portion for closing the access opening defined therein. Commonly, the cover includes a pierceable, self-closing membrane which permits the insertion of a hypodermic needle or similar instrument therethrough for the purpose of extracting a product sample from the conduit portion without removing the cover. An example of a fitting having a neck portion and cover of the aforedescribed type is shown and described in U.S. Pat. No. 3,779,082.
Inasmuch as it is desirable for sanitation purposes that the fitting be at all times relatively clean, a limitation associated with conventional sample fittings such as the one described in the referenced patent relates to the capacity of the neck portion thereof to be maintained clean. For example, the neck portion and cover of the fitting described in the referenced patent are in direct engagement with one another by means of a threaded connection. It has been found that the thread grooves of such a threaded connection provide collection channels for the accumulation of the viscous product when, due to product spillage or otherwise, the outer surface of the neck portion is exposed to the product. If, of course, viscous product is permitted to collect within the thread grooves, bacteria spawned therein could contaminate the product contained within the fitting conduit portion and the piping within which the fitting is connected.
Another limitation associated with a fitting such as the one described in the referenced patent relates to the relatively high cost of the pierceable membrane supported within the fitting cover. Such a high cost is believed to be due, at least in part, to the relatively large quantity of material contained within the body of the membrane. Furthermore, inasmuch as the membrane is commonly replaced with a new one between selected product processing cycles, the relatively high cost of the membrane contributes to a relatively high maintenance cost of the fitting.
Accordingly, it is an object of the present invention to provide a new and improved sampler fitting through which a sample of a viscous product can be extracted.
Another object of the present invention is to provide such a fitting wherein the cleanliness thereof can be easily maintained.
Still another object of the present invention is to provide such a fitting having components absent of thread grooves in which the viscous product is apt to collect.
Yet still another object of the present invention is to provide such a fitting wherein the cover thereof is maintained out-of-contact with the neck portion.
A further object of the present invention is to provide such a fitting including a pierceable, self-closing membrane which can easily be replaced and which is relatively inexpensive.
A still further object of the present invention is to provide such a fitting which is economical to construct and effective in operation.